org.openimaj.image.feature.local.aggregate

Class BlockSpatialAggregator<T,AGGREGATE extends FeatureVector & Concatenatable<AGGREGATE,AGGREGATE>>

java.lang.Object

org.openimaj.image.feature.local.aggregate.BlockSpatialAggregator<T,AGGREGATE>

Type Parameters:

T - Primitive array type of the backing array of each local feature

AGGREGATE - Type of the aggregate FeatureVector produced

All Implemented Interfaces:

SpatialVectorAggregator<ArrayFeatureVector<T>,SpatialLocation,Rectangle>

public class BlockSpatialAggregator<T,AGGREGATE extends FeatureVector & Concatenatable<AGGREGATE,AGGREGATE>>
extends Object
implements SpatialVectorAggregator<ArrayFeatureVector<T>,SpatialLocation,Rectangle>

A BlockSpatialAggregator performs spatial pooling of local features by grouping the local features into non-overlapping, fixed-size spatial blocks, and applying a VectorAggregator (i.e. a BagOfVisualWords) to the features within each block before combining the aggregated results into a single vector (by passing through the blocks in a left-right, top-bottom fashion).

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Field Summary

Fields

Modifier and Type	Field and Description
protected int	blocksX
protected int	blocksY
protected VectorAggregator<ArrayFeatureVector<T>,AGGREGATE>	innerAggregator

Constructor Summary

Constructors

Constructor and Description
BlockSpatialAggregator(VectorAggregator<ArrayFeatureVector<T>,AGGREGATE> innerAggregator, int blocksX, int blocksY) Construct with the given aggregator and number of blocks in the X and Y dimensions.

Method Summary

Modifier and Type	Method and Description
AGGREGATE	aggregate(List<? extends LocalFeature<? extends SpatialLocation,? extends ArrayFeatureVector<T>>> features, Rectangle bounds) Aggregate the given features into a vector.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

innerAggregator

protected VectorAggregator<ArrayFeatureVector<T>,AGGREGATE extends FeatureVector & Concatenatable<AGGREGATE,AGGREGATE>> innerAggregator

blocksX

protected int blocksX

blocksY

protected int blocksY

Constructor Detail

BlockSpatialAggregator

public BlockSpatialAggregator(VectorAggregator<ArrayFeatureVector<T>,AGGREGATE> innerAggregator,
                              int blocksX,
                              int blocksY)

Construct with the given aggregator and number of blocks in the X and Y dimensions.

Parameters:

innerAggregator - the aggregator

blocksX - the number of blocks in X

blocksY - the number of blocks in Y

Method Detail

aggregate

public AGGREGATE aggregate(List<? extends LocalFeature<? extends SpatialLocation,? extends ArrayFeatureVector<T>>> features,
                           Rectangle bounds)

Description copied from interface: SpatialVectorAggregator

Aggregate the given features into a vector. The features are assumed to have spatial locations within the given bounds; typically this might be the bounds rectangle of the image from which the features were extracted.

Specified by:

aggregate in interface SpatialVectorAggregator<ArrayFeatureVector<T>,SpatialLocation,Rectangle>

Parameters:

features - the features to aggregate

bounds - the bounds in which the features were extracted

Returns:

the aggregated vector